We've all seen those mini cellphone rechargers at airports, but Duracell has released a line of rechargeable pocket chargers that can refill any USB-compatible device (like iPhones) through compatibility with your own adapters. And our favorite model is cheap.

The Price

Duracell Instant Charger: $20
Duracell Powerhouse Charger: $50

The Verdict

Duracell's Instant Charger is a perfectly executed little gadget. And its older sibling, the Powerhouse Charger, isn't so bad either.

There's nothing complicated going on. These chargers are essentially a USB port loaded hooked to a lithium ion battery. But it just so happens, that's all you need.

The Instant Charger is the smallest of the line and by far my most favorite. It's small and nearly weightless in your hand, ornamented with a more-polished-than-necessary design. But after charging (via mini USB), the Instant Charger stores just enough power to refill your iPhone about halfway (for 180 minutes of 3G talk time)—or just snag a few more shots out of a digital camera—or power an e-reader—or pretty much whatever you want.

With no unnecessary buttons or (you'll only need to navigate an on/off switch) and a simple indicator light (red when charging, green when charged), Duracell's Instant Charger is a wonderful unitasker.

I wish the Powerhouse Charger had all the polish you see in the Instant version. Not counting a legitimately neat Mini-USB arm, from the less thoughtful finish to indicator lights that aren't readable in daylight, the Powerhouse just seems...cheap (which is ironic, given that the Powerhouse is supposed to be this line's Cadillac). But it stores enough power to charge an iPhone 3G or Blackberry Curve 1.2 times, or an iPod nano 4 times.

Most iPhone charging solutions involve cases we don't need or want, and they can easily reach $100. Now Duracell has a few products that can handle pretty much any USB device you can throw at them. And starting at $20, we can live with the investment. [Duracell]